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RT Journal Article
SR Electronic
T1 Quantitative Diffusion-Weighted and Dynamic Susceptibility-Weighted Contrast-Enhanced Perfusion MR Imaging Analysis of T2 Hypointense Lesion Components in Pediatric Diffuse Intrinsic Pontine Glioma
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 315
OP 322
DO 10.3174/ajnr.A2277
VO 32
IS 2
A1 Löbel, U.
A1 Sedlacik, J.
A1 Reddick, W.E.
A1 Kocak, M.
A1 Ji, Q.
A1 Broniscer, A.
A1 Hillenbrand, C.M.
A1 Patay, Z.
YR 2011
UL http://www.ajnr.org/content/32/2/315.abstract
AB BACKGROUND AND PURPOSE: Focal anaplasia characterized by T2 hypointensity, signal-intensity enhancement on postcontrast T1-weighted MR imaging and restricted water diffusion has been reported in a patient with juvenile pilocytic astrocytoma. We identified T2HOF with these MR imaging characteristics in children with DIPG and hypothesized that these represent areas of focal anaplasia; and may, therefore, have increased perfusion properties and should be characterized by increased perfusion. Thus, we used DSC to investigate our hypothesis. MATERIALS AND METHODS: We retrospectively reviewed the baseline MR imaging scans of 86 patients (49 girls, 37 boys; median age, 6.1 years; range, 1.1–17.6 years) treated for DIPG at our hospital (2004–2009). T2HOF with the described MR imaging characteristics was identified in 10 patients. We used a region of interest−based approach to compare the ADC, FA, rCBV, rCBF, and rMTT of T2HOF with those of the typical T2HRT. RESULTS: The ADC of T2HOF with the specified MR imaging characteristics was significantly lower than that of T2HRT (range, 0.71–1.95 μm2/ms versus 1.36–2.13 μm2/ms; P &lt; .01); and the FA (range, 0.12–0.34 versus 0.07–0.24; P = .03) and rCBV (range, 0.4–2.62 versus 0.23–1.57; P = .01) values of T2HOFs were significantly higher. CONCLUSIONS: Our data suggest that T2HOF in DIPG may represent areas of focal anaplasia and underline the importance of regional, rather than global, tumor-field analysis. T2HOF may be the ideal target when stereotactic biopsy of tumors that present with an inhomogeneous T2 signal intensity is considered. ADCapparent diffusion coefficientAIFarterial input functiona.u.arbitrary unitsCBFcerebral blood flowCBVcerebral blood volumeDIPGdiffuse intrinsic pontine gliomaDSCdynamic susceptibility-weighted contrast-enhanced perfusion MR imagingDTIdiffusion tensor imagingDWIdiffusion-weighted imagingFAfractional anisotropyGBCAgadolinium-based contrast agentGMgray matterrCBFrelative cerebral blood flowrCBVrelative cerebral blood volumerMTTrelative mean transit timeT2HOFT2 hypointense focus with postcontrast signal enhancement and diffusion restrictionT2HRTtypical T2 hyperintense tumorWMwhite matter